Square cap for test tube



FIG. 1 is a perspective top view of a square cap for a test tube, showing my new design;

FIG. 2 is a perspective bottom view thereof;

FIG. 3 is a front view thereof with a rear view, left side view, and right side view being a mirror image;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a perspective bottom view of the square cap for a test tube depicted in use as attached to a test tube.

The broken line showing of a test tube is for the purpose of illustrating environmental structure and forms no part of the claimed design. 

CLAIM The ornamental design for a square cap for a test tube, as shown and described. 